The project will evaluate newer drug treatments for tardive dyskinesia and related conditions. It will attempt to improve our knowledge about the variability of such movements over time in the same patients and will attempt to develop better methods for assessing movement disorders in psychiatric patients. The potential use of an antiparkinsonian agent, Benztropine, as a dyskinesia undercovering agent will be explored. Surveys of special groups of psychiatric patients resident in the community will be undertaken.